// Copyright 2018 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package stream
import (
"context"
"errors"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/metrics"
"github.com/ethereum/go-ethereum/p2p/discover"
"github.com/ethereum/go-ethereum/swarm/log"
"github.com/ethereum/go-ethereum/swarm/network"
"github.com/ethereum/go-ethereum/swarm/spancontext"
"github.com/ethereum/go-ethereum/swarm/storage"
opentracing "github.com/opentracing/opentracing-go"
)
const (
swarmChunkServerStreamName = "RETRIEVE_REQUEST"
deliveryCap = 32
)
var (
processReceivedChunksCount = metrics.NewRegisteredCounter("network.stream.received_chunks.count", nil)
handleRetrieveRequestMsgCount = metrics.NewRegisteredCounter("network.stream.handle_retrieve_request_msg.count", nil)
requestFromPeersCount = metrics.NewRegisteredCounter("network.stream.request_from_peers.count", nil)
requestFromPeersEachCount = metrics.NewRegisteredCounter("network.stream.request_from_peers_each.count", nil)
)
type Delivery struct {
db *storage.DBAPI
overlay network.Overlay
receiveC chan *ChunkDeliveryMsg
getPeer func(discover.NodeID) *Peer
}
func NewDelivery(overlay network.Overlay, db *storage.DBAPI) *Delivery {
d := &Delivery{
db: db,
overlay: overlay,
receiveC: make(chan *ChunkDeliveryMsg, deliveryCap),
}
go d.processReceivedChunks()
return d
}
// SwarmChunkServer implements Server
type SwarmChunkServer struct {
deliveryC chan []byte
batchC chan []byte
db *storage.DBAPI
currentLen uint64
quit chan struct{}
}
// NewSwarmChunkServer is SwarmChunkServer constructor
func NewSwarmChunkServer(db *storage.DBAPI) *SwarmChunkServer {
s := &SwarmChunkServer{
deliveryC: make(chan []byte, deliveryCap),
batchC: make(chan []byte),
db: db,
quit: make(chan struct{}),
}
go s.processDeliveries()
return s
}
// processDeliveries handles delivered chunk hashes
func (s *SwarmChunkServer) processDeliveries() {
var hashes []byte
var batchC chan []byte
for {
select {
case <-s.quit:
return
case hash := <-s.deliveryC:
hashes = append(hashes, hash...)
batchC = s.batchC
case batchC <- hashes:
hashes = nil
batchC = nil
}
}
}
// SetNextBatch
func (s *SwarmChunkServer) SetNextBatch(_, _ uint64) (hashes []byte, from uint64, to uint64, proof *HandoverProof, err error) {
select {
case hashes = <-s.batchC:
case <-s.quit:
return
}
from = s.currentLen
s.currentLen += uint64(len(hashes))
to = s.currentLen
return
}
// Close needs to be called on a stream server
func (s *SwarmChunkServer) Close() {
close(s.quit)
}
// GetData retrives chunk data from db store
func (s *SwarmChunkServer) GetData(ctx context.Context, key []byte) ([]byte, error) {
chunk, err := s.db.Get(ctx, storage.Address(key))
if err == storage.ErrFetching {
<-chunk.ReqC
} else if err != nil {
return nil, err
}
return chunk.SData, nil
}
// RetrieveRequestMsg is the protocol msg for chunk retrieve requests
type RetrieveRequestMsg struct {
Addr storage.Address
SkipCheck bool
}
func (d *Delivery) handleRetrieveRequestMsg(ctx context.Context, sp *Peer, req *RetrieveRequestMsg) error {
log.Trace("received request", "peer", sp.ID(), "hash", req.Addr)
handleRetrieveRequestMsgCount.Inc(1)
var osp opentracing.Span
ctx, osp = spancontext.StartSpan(
ctx,
"retrieve.request")
defer osp.Finish()
s, err := sp.getServer(NewStream(swarmChunkServerStreamName, "", false))
if err != nil {
return err
}
streamer := s.Server.(*SwarmChunkServer)
chunk, created := d.db.GetOrCreateRequest(ctx, req.Addr)
if chunk.ReqC != nil {
if created {
if err := d.RequestFromPeers(ctx, chunk.Addr[:], true, sp.ID()); err != nil {
log.Warn("unable to forward chunk request", "peer", sp.ID(), "key", chunk.Addr, "err", err)
chunk.SetErrored(storage.ErrChunkForward)
return nil
}
}
go func() {
var osp opentracing.Span
ctx, osp = spancontext.StartSpan(
ctx,
"waiting.delivery")
defer osp.Finish()
t := time.NewTimer(10 * time.Minute)
defer t.Stop()
log.Debug("waiting delivery", "peer", sp.ID(), "hash", req.Addr, "node", common.Bytes2Hex(d.overlay.BaseAddr()), "created", created)
start := time.Now()
select {
case <-chunk.ReqC:
log.Debug("retrieve request ReqC closed", "peer", sp.ID(), "hash", req.Addr, "time", time.Since(start))
case <-t.C:
log.Debug("retrieve request timeout", "peer", sp.ID(), "hash", req.Addr)
chunk.SetErrored(storage.ErrChunkTimeout)
return
}
chunk.SetErrored(nil)
if req.SkipCheck {
err := sp.Deliver(ctx, chunk, s.priority)
if err != nil {
log.Warn("ERROR in handleRetrieveRequestMsg, DROPPING peer!", "err", err)
sp.Drop(err)
}
}
streamer.deliveryC <- chunk.Addr[:]
}()
return nil
}
// TODO: call the retrieve function of the outgoing syncer
if req.SkipCheck {
log.Trace("deliver", "peer", sp.ID(), "hash", chunk.Addr)
if length := len(chunk.SData); length < 9 {
log.Error("Chunk.SData to deliver is too short", "len(chunk.SData)", length, "address", chunk.Addr)
}
return sp.Deliver(ctx, chunk, s.priority)
}
streamer.deliveryC <- chunk.Addr[:]
return nil
}
type ChunkDeliveryMsg struct {
Addr storage.Address
SData []byte // the stored chunk Data (incl size)
peer *Peer // set in handleChunkDeliveryMsg
}
func (d *Delivery) handleChunkDeliveryMsg(ctx context.Context, sp *Peer, req *ChunkDeliveryMsg) error {
var osp opentracing.Span
ctx, osp = spancontext.StartSpan(
ctx,
"chunk.delivery")
defer osp.Finish()
req.peer = sp
d.receiveC <- req
return nil
}
func (d *Delivery) processReceivedChunks() {
R:
for req := range d.receiveC {
processReceivedChunksCount.Inc(1)
// this should be has locally
chunk, err := d.db.Get(context.TODO(), req.Addr)
if err == nil {
continue R
}
if err != storage.ErrFetching {
log.Error("processReceivedChunks db error", "addr", req.Addr, "err", err, "chunk", chunk)
continue R
}
select {
case <-chunk.ReqC:
log.Error("someone else delivered?", "hash", chunk.Addr.Hex())
continue R
default:
}
chunk.SData = req.SData
d.db.Put(context.TODO(), chunk)
go func(req *ChunkDeliveryMsg) {
err := chunk.WaitToStore()
if err == storage.ErrChunkInvalid {
req.peer.Drop(err)
}
}(req)
}
}
// RequestFromPeers sends a chunk retrieve request to
func (d *Delivery) RequestFromPeers(ctx context.Context, hash []byte, skipCheck bool, peersToSkip ...discover.NodeID) error {
var success bool
var err error
requestFromPeersCount.Inc(1)
d.overlay.EachConn(hash, 255, func(p network.OverlayConn, po int, nn bool) bool {
spId := p.(network.Peer).ID()
for _, p := range peersToSkip {
if p == spId {
log.Trace("Delivery.RequestFromPeers: skip peer", "peer", spId)
return true
}
}
sp := d.getPeer(spId)
if sp == nil {
log.Warn("Delivery.RequestFromPeers: peer not found", "id", spId)
return true
}
err = sp.SendPriority(ctx, &RetrieveRequestMsg{
Addr: hash,
SkipCheck: skipCheck,
}, Top)
if err != nil {
return true
}
requestFromPeersEachCount.Inc(1)
success = true
return false
})
if success {
return nil
}
return errors.New("no peer found")
}
